On January 17, 1994, a magnitude-6.7 earthquake struck los angeles—The Northridge Earthquake. It was then that the nation recognized the presence a very important structural flaw that plagued lots of buildings within the nation’s most earthquake-prone cities. The bottom floor of the Northridge Meadows apartment complex collapsed beneath the 2 floors above it. Sixteen residents, all on the first floor, died from this incident. Why did the complex when so many other structures remained standing? Simply because the Northridge Meadows was a soft-story building.
A large number of homes, together with apartments and business buildings, have a ‘soft story’ element. These houses may be required to conform with the Los Angeles Earthquake Retrofit Program. Many people are usually not conversant in this term but it is not difficult to understand. A soft story building is used to describe a building with three or more stories located over ground level and windows, large doors, commercial spaces and other openings in a place where a shear wall is typically required to provide stability.
A soft story building is almost always an apartment building with rooms above carport, garage or open areas. The sort of building is just not designed for the transmission of shear or lateral forces between the earth and the stories above. Without necessary strengthening, such buildings are prone to structural damage during an earthquake. The first floor of a building is weak because it lacks sufficient shear walls. Beams surrounding open parking areas are usually not strong enough to support the entire building during an earthquake.
The city of LA, in 2015, passed ordinances (Ordinance 183893 and Ordinance 184081) to set up necessary requirements for soft-story buildings in Los Angeles to promote public protection and reduce structural deficiencies as a consequence of earthquakes. The ordinance requires retrofitting of all of the pre-1978 smooth-story structures. The department of public safety has compiled a list of buildings that require a seismic retrofit and the Los Angeles Earthquake Retrofit Program outlines that each one requirements will have to be complied with by the year 2022.
Any apartment constructed earlier than 1980 is more likely to be part of the 13,500 buildings listed by the department and the individuals residing in Hollywood, Westside and San Fernando Valley will be affected due to this area the most as these areas having lots of old apartments. Apartment buildings are fairly common in these locations however their age and design leave them at prone to failure during seismic movements. Soft story buildings constructed between 1950 and 1980 do not meet the latest seismic standards and require a seismic retrofit to obtain the strength to resist shaking during an earthquake. This applies specifically to buildings built along and close to fault lines.
Seismic Retrofit Process
To implement the ordinance, Los Angeles building officials have identified the affected structures and notified the owners to start the retrofitting process. Owners will have two years time, after receiving the compliance order, to submit plans of retrofitting or demolition or the proof that the building does not need retrofitting. The entire process must be completed within seven years of getting the order.
The process of Seismic Retrofit, though not difficult, requires great attention and planning. The first step is getting the engineering and architectural plans approved by the department for compliance with the new law. The construction can commence once the plans are approved. Tenants will be affected by the retrofit process and they should be notified in advance. Trenches are dug to install new steel beams in place of wooden beams to provide sufficient strength to the soft story.
The purpose of seismic retrofitting process is to counteract the main forces induced by earthquake causing damage to buildings. It involves installing engineered metal connectors and other reinforcement materials at stress points throughout the foundation of the soft story building.
These connectors convert the loosely connected parts of a building into a unified structure that stays together when affected by seismic forces which can easily tear weak buildings apart. A seismic retrofit process helps minimize damage of earthquake thereby reducing repair costs after a seismic event.
What We Offer
RetroFitting360, Inc. is a Los Angeles based retrofitting contractor that offers the following:
Our site evaluation is 100% free of charge. One of our RetroFitting360 retrofit specialists will walk through your property, analysing and assessing conditions in order to outline all necessary information as well as measures to be taken to comply with the Ordinance. Following the evaluation, you’ll receive an initial proposal with an estimated cost of engineering and construction.
If your building is affected and must adhere to the Los Angeles Earthquake Retrofit Program, you can start the process today by availing our free evaluation service that examines your building to get you a free estimate of the design and permit.
We will find the most effective and ordinance compliant retrofit options for your building making sure that it causes minimum impact on the existing structure. Our staff is specialized and trained at seismic evaluation and retrofit processes and uses an approved methodology to provide a detailed engineering analysis of the existing structure. We provide drawings for permit and all other documentation to be submitted to the Building Department for review and approval.
Our team of designers make sure that the drawings are perfect so that construction can start at the earliest. Once the plan is approved, we provide the necessary structural assistance to make sure that the construction is implemented according to the plan and meets the City requirements.
As a leading provider of seismic retrofitting of existing buildings in Los Angeles region, we focus on construction efficiency and help you identify the most cost-effective solution. We have civil, architectural and structural staffs that provide the required service to modify the floor and site plans to acquire permits.
We are committed to turning your soft-story buildings in Los Angeles retrofit process into an easy, quick and painless affair. Whether you have received a notice for the seismic retrofit to comply with the Los Angeles Soft-Story Retrofit Program ordinance, concerned about your apartment’s foundation or interested in seismic strengthening to ensure your safety during earthquake, you can contact us to get a free Los Angeles soft-story retrofit evaluation of your property and the most cost-effective solution.
